Process for aftertreatment of freshly colored polyamide fibers



United States Patent 3,490,860 PROCESS FOR AFTERTREATMENT OF FRESHLY.

COLORED POLYAMIDE FIBERS Karl Soiron, Riehen, Switzerland, Hans Rafael,Well am Rhine, Germany, and Walter Stockar, Munchenstem, Basel-land,Switzerland, assignors to J. R. Geigy A.G., Basel, Switzerland N0Drawing. Original application July 19, 1963, Ser. No. 296,392. Dividedand this application Sept. 5, 1967, Ser. No. 665,223

Im. 01. D06m 3/40 US. Cl. 8-74 10 Claims ABSTRACT OF THE DISCLOSURE Thisapplication discloses and claims only subject matter disclosed in ourpending application Ser. No. 637,309, filed May 9, 1967, as acontinuation application of our application Ser. No. 515,774, filed Oct.22, 1965 as a divisional application under Rule 147 of our applicationSer. No. 296,392, filed July 19, 1963, both lastmentioned applicationsbeing now abandoned.

Description of the invention This invention relates to improvements indyeing and printing on polyamide fibers as well as, industrial products,the dyed and printed polyamide fibers treated according to theinvention.

Hitherto, wool and other polyamide fibers including nylon and the likesynthetic polyamide fibers which had been dyed with reactive dyestuffscontaining per molecule at least one substituent which can be split offas an anion during the dyeing and/or after-treatment of the dyed fibers,had to be subjected to an after treatment in an aqueous basic medium ofa pH of preferably about 7.5 or higher which contains, for example,sodium hydroxide, sodium carbonate, or preferably ammonia orhexamethylenetetramine as the basic agent.

This known alkaline after-treatment, which serves to fix on the fibersstill unreacted dyestulf present in the dyed goods, suffers from thedrawback that the polyamide fibers can be injured by the alkaline mediumand particularly by a subsequent drying step if the same is carried outdirectly on the after-treated fibers.

Therefore, in the known dyeing methods, the aftertreatment with analkaline medium is followed usually by a further treatment in an acidmedium prior to final drying of the dyed or printed fibers.

Another drawback of the after-treatment with alkaline agents such asammonia or hexarnethylenetetramine re "ice sides in the tendency of thealkaline bath to remove at least part of the still unreacted dyestufffrom the fibers, whereby an exact control of the shade of the fixeddyeings or prints is made very diflicult.

It is, therefore, an object of the present invention to provide, in aprocess of dyeing or printing polyamide fibers with reactive dyestuffsof the type described, an after-treatment of the dyed fibers for thepurpose of fixing still unreacted residual dyestulf on the fibers, whichaftertreatment does not injure the fibers, permits of drying theafter-treated fibers directly without further intermediate treatments,and allows for a more exact control in producing a desired shade.

These objects are attained by the treatment according to the invention,which comprises, as an after-treatment in dyeing and printing processesfor producing colored polyamide fibers by heating and thereby reactingsaid fibers with relative dyestufi, i.e. dyestuff containing at leastone mobile substituent capable of being split off as anion, in anaqueous acid medium, preferably at a pH of about 4.5 to 5, and,preferably, with subsequent rinsing of the colored fibers in water of atemperature of about 10 to preferably 60, and not more than C., anddrying,

(I) introducing the freshly colored, and preferably immediatelysubsequently rinsed, fibers, directly thereafter and prior to drying,into an aqueous solution of a condensation product of (a) a naphthalenesulfonic acid, in particular a monoto trisulfonic acid, and preferablynaphthalene-Z-monosulfonic acid, or a 1,2,3,4-tetrahydronaphthalenesulfonic acid,

(b) fromabout 0.5 to 1.5, and preferably from 0.8 to 1.2 parts byweight, per part by Weight of (a), of a compound of the formulaHO-phenylene-SO -phenylene-OH, preferably 4,4-dihydroxy-diphenylsulfone,and

(c) from about 0.1 to 0.2, and preferably 0.1 part by weight, per partby weight of (a), of formaldehyde, in aqueous, preferably about30%-solution,

(II) if necessary, adjusting the pH of the aqueous solution to about 4to 5.5, and preferably to 4.5 to 5, by the addition of acid, such asacetic or formic acid, and preferably of acetic acid, and

(III) heating the said aqueous solution and the colored fibers thereinfor a short time, about 10 to 60, and preferably 15 to 30 minutes, at atemperature of about 20 to 100, and preferably 60 to C.

According to another mode of carrying out the treatment according to theinvention in practice, the condensation product used as the fixing agentin the aqueous acid solution of steps (I) to (III) described supra, isproduced by condensation of (a) a u,w-dlChlOrO- or a,w-dibromoalkane offrom 2 to 7 carbon atoms, or w,w-dichloro-dialkylether with a total offrom 4 to 8 carbon atoms, with (b) a tertiary saturated aliphatic aminewith a total of from 6 to 24 carbon atoms and from two to four aminonitrogen atoms,

in such molar ratio of (a):(b) that approximately one halogen atom ispresent in the condensation reaction for every amino nitrogen atom.

According to yet another mode of carrying out the treatment according tothe invention in practice, there is used in the aqueous solution ofsteps (i) to (Ill) supra, in lieu of the above-mentioned condensationproducts, a product produced by the condensation of (a) dicyanodiamide,

(b) at least one mole, per mole of (a), or an excess thereover, of anammonia donator which is either urea or an ammonium salt of a mineralacid capable of splitting off ammonia, and

(c) at least two moles, per mole of (a), or an excess thereover, offormaldehyde in aqueous, preferably 30% by weight, solution. Aconcentration of about 0.5 gram of condensation product per liter ofsolution is the minimum.

In the second and third modes of the treatment according to theinvention described above, the addition of acid to the solution inaccordance with step II, supra, is mandatory.

As polyamide fibers, those of natural origin, above all wool and silk,but also synthetic polyamide fibers such as the various kinds of nylone.g. nylon 6, nylon 66, and nylon 11 (Rilsan), are suitable for theafter-treatment according to the invention.

These polyamide fibers are dyed by known methods in a dyestuff solutionwhich, in addition to the dyestuffs mentioned, can also contain theauxiliaries usual in wool dyeing, e.g. salts such as sodium sulfate orammonium sulfate and/ or dilute acids, e.g. acetic or formic acid, and/or wetting agents, e.g. condensation products of fatty acids having atleast 8 carbon atoms and lower alkanolamines such as are described inUS. Patent 2,089,212.

The aforesaid fibers are printed by known processes in neutral or acidmedium in the presence of thickeners and, optionally, urea.

The after-treatment according to the invention with the solution of thecondensation products is preferably performed in a solution whichcontains these products in a concentration of about 0.5 to 3 g. perliter, furthermore, optionally, other additives usual in textile dyeing,and finally, acid, e.g. acetic or formic acid, as mentioned above.

The aforesaid condensation products suitable for use in the firstabove-described mode of carrying out the invention in practice areproduced as described in German Patent 611,671, issued Apr. 5, 1935;those suitable for use in the second mode of practicing the inventiondescribed above, are produced as described in German Patent 894,237,issued Oct. 22, 1953. This class of condensation products is obtainedby'reacting the components mentioned above at a raised temperature,about 50 to 140 C., possibly in the presence of diluents, e.g. butylalcohol, ethylene glycol or diethylene glycol. Among the saturatedaliphatic tertiary polyamines defined above, there are:

Di-, triand tetra-amines such as N,N'-tetramethylhexamethylenediamineand homologues, N,N,N-pentamethyl diethylenetriamine, N,N',N,N'hexamethyltriethylenetetramine as well as industrial mixtures thereofalso.

Examples of a,w-dihalogen alkanes are 1,2-dichloroor 1,2-dibromo-ethane,1,3-dichloro-propane, 1,4-dichlorobutane, 1,5-dich1oropentane,1,6-dichlorohexane; w,w-dihalogen ethers are, e.g.,8,fi'-dichlorodiethyl ether, ethylene glycol-di-fi-chloroethyl ether,fl,,8'-di-(2-chloroethoxy)-di-ethyl ether, ,'y'-dichloropropyl ether aswell as glycerin dichlorohydrin. The reaction products are mosteffective when the ratio of the reaction components is so chosen thatthere is about one halogen atom per N atom, so that, for example, onusing a triamine, two mols of amine are quaternized with three mols ofa,w-dihalogen alkane. Particularly good results are obtained with thecondensation product of 2 mols of N,N",N"-pen.t me hyldiethylenetriamineand 3 mols of B,fl'-dichlorodiethyl ether.

The condensation products usable in the third mode of carrying out thetreatment according to the invention are produced from dicyanodiamideand the ammonium salt of a strong mineral acid or urea, andformaldehyde, as described in German Patent 929,642, issued Oct. 22,1953. Best results are obtained with compounds from this class which areproduced in accordance with Example 2 of German Patent 929,642.

The reactive dyestuffs used according to the invention can be of themost varied classes of dyestuffs. Preferably they are nitro, azo,anthraquinone or phthalocyanine dyestuffs, which classes excel instability. They contain watersolubilizing, acid, salt-forming groups,mainly sulfonic acid groups, possibly also carboxyl groups or sulfamylgroups, in the latter case, among others, also acylated sulfamyl groups,e.g. disulfimide and carbonyl sulfimide groups.

The advantages attained according to the invention are particularlyimpressive when the reactive dyestuffs conventionally used for the fastdyeing of cellulose are used which contain sulfonic acid groups, e.g. 2to 4, per dyestuff molecule. Thus, examples of dyestuffs, dyeings ofwhich are especially suitable for use in the treatment according to theinvention are nitrodiarylamine sulfonic 'acids, metal-free monoandpoly-azo dyestuffs, heavy metal-containing, e.g. chromium orcobalt-containing, 0,0- dihydroxy-, o-hydroxy-o-carboxyando-hydroxy-o-amino-mono-azo and dis-azo dyestuffs, copper-containingformazane dyestuffs, 1-amino-4-phenylamino anthraquinone dyestuffs, andcopper phthalocyanines with substituted sulfamyl groups, all of whichpreferably contain at least two sulfonic acid groups.

Mobile substituents which can be split off as anion are mainly: radicalsof strong acids, in particular halogen atoms, of these preferablychlorine, or bromine or fluorine, -the mobility of which is due, forexample, to the bond at fi-carbon atoms in negatively substitutedorganic radicals, at S0 groups in the case of fluorine, at carbon atomsadjacent to tertiary ring nitrogen in nitrogen heterocycles of aromaticcharacter, in this case preferably 6- membered heterocycles having atleast two tertiary ring nitrogen atoms-aromatically bound halogen atomsin oand/ or p-position to one (or more) electrophilic group(s) inparticular fluorine or chlorine atoms; further, for example, the radicalof sulfuric acid in sulfated fi-hydroxyalkyl compounds, e.g. in sulfatedfi-hydroxy-alkyl sulfonyl and sulfamyl groups; or the radical ofhydroxy-aryl compounds in O-aryl urethane groups.

Dyestuffs usable according to the invention contain the substituentwhich can be split off as anion, for example, in the form of B-chloroorfl-bromo-fatty acid amide groups, in which case fl-chlorocrotonic acidamide or 8- bromopropionic acid amide groups are preferred; or the saidsubstituent is in the form of fluoroor chloro-nitrobenzoylamino groupsor fluoroor chloro-nitrobenzene sulfonylamino groups in which thefluorine or chlorine atoms are in the 0- and/or p-position to the nitrogroup or groups; or, preferably, it is in the form of chloroorbromo-diazinylamino or triazinylamino groups, in which case it is inparticular in the form of monochloroor dichloro-s-triazinylamino groupsand, preferably, dior trichloropyrimidylamino groups. Dyestuffs with atleast one dior tri-halogen pyrimidylamino group and at least 2 sulfonicacid groups are preferred in the dyeing and printing processescomprising the after-treatment according to the invention.

An advantage of the treatment according to the invention over the knownprocesses is the elimination of an alkaline after-treatment with, forexample ammonia or hexamethylenetetramine. This advantage becomes mostapparent in the dyeing and printing of wool which is sensitive toalkali, as the danger of injury to the fibers inherent in, the alkalineafter-treatment is avoided.

Moreover, the control of producing the desired shade more exactly isfacilitated since changes in shade due to shifting of the pH of thedyeing medium from acid to alkaline and possibly back to acid areavoided.

.6 Patent No. 2,089,212), and 4 parts of 80% acetic acid.

The goods are introduced into the liquor at 50, dyeing is performed forminutes at this temperature, the bath Dyeings or prints on polyamidefibers attained according to the invention are distinguished by pure,strong and 5 gs gfigg g z g fi g zg gg ig and dyemg 18 even shades andgood fastness properties. In particular, they have remarkable wetfastness properties, for example gf ggg ifi a g gg ggi g;: g 2 2 522 5 3Ygfgaigigi mlnmg and persplrafion and g. per liter of a condensationproduct of formaldehyde with The following non lim'itative examplesillustrate the 10 dihydroxyd phenyl sulfone and naphthalene sul fonicacids, vention Where not otherwise stated arts and manta es theproduction of which condensation product is described 9 pa g below, aswell as 0.25 g. per liter of 80% acetic acid. are given by welght. Therelationship of parts by weight to Valuable red d ein S are obtained inthis wa which are parts by volume is as that of grams to cubiccentimeters. very wet fast y g y The temperatures are glven m degreescenngrade The condensation product mentioned is obtained as EXAMPLE 1follows: I

100 parts of the sulfonating mixture, obtained by heatgg 52 238 2 m figggg 12 23 parts of a dye liquor ing for several hours at 140160, 520parts of naphtha- 2 lene and 560 parts of concentrated sulfuric aciduntil wa- 4 Parts Ufa dyestllfi 0f the formula 0 ter solubility isattained, are heated for about 1 hour at 01 c 105110 with 100 parts of adihydroxydiphenyl sulfone, parts of water and 45 parts of formaldehyde(30%). The dihydroxydiphenyl sulfone is obtained by heating 540 HO NH C25 parts of phenol and 180 parts of oleum for 3 hours N=0 at l-180 anddistilling off excess phenol. By using, instead of the dyestuff given inExample 1, the dyestuffs listed in column 2 of the following table, and303E S0311 S0311 otherwise following the procedure described in saidexam- 30 ple, wool dyeings of the shade given in column 3 and of 0.5part of a condensation product of 1 mol of oleic acid good fastness towashing, perspiration and sea water are and 2 mols of diethanolamine(Example 5 of US. obtained.

TABLE I No Dyestnfi Shade on wool 1 CH3 Greenish- N & (31 yellow. so 11c a l \C--N=N l N N O-N-C H I I HOaS NHO\ %CCl ll OH CH 2 (I31Reddish-yellow.

0 H C\ S a H (HJ \blr N=N -NH-O /C--Cl CH3 S OaH 3 (")1 Red.

t HO NH--C C-C1 S0311 S0311 SOsH 4 (H) NH; Blue.

-SO3H g NH 0311 w N N TABLE I Shade on wool Dyestufi Turquoise blue.

(wherein Cu-Ihtc, is the copper phthalocyanine radical) w e B no N N B BB 0 N m N m N m 1 1 N N N i N 0 N N m c N l\ 1 1 C C C|C CIIC C 2 1 o mm N m 4 H N|o u N J N N 0| ml N N N C- N N N N N N NN N N N I s H 1....2 i m a vm H m w 0. O AM N l a a. @N o O O 0 .5 H n H TABLE IContinued No. Dyestufi Shade on wool 12 S0311 Greenish so H I yellow. I a

Q K i o H o-N NH I 13 HO NHa Blue-black.

HO SO-CHzCH2SOzC -N=N N=NSOzCH2CHz-OSOaH H035 SOaH 14 C1 Blue.

Hogs 0-Cu 0 NH-C\ N N=C N=N N=N I NHC SOaH H038 SOaH SOaH EXAMPLE 2 Thegoods are entered into the liquor at 40, dyeing Wool is printed with aprinting paste of the following 35 Perform?d for mlmltes at thistemperature, the bath composition; is brought to the boil within minutesand dyeing is continued for 45 minutes at the boil.

30 parts of the dyestufi of the formula After dyeing, the goods are wellrinsed and treated for J: 20 minutes at 60-80 in fresh bath whichcontains 0.75 g. per liter of the formaldehyde/dihydroxydiphenylsul- H0NH--C N fone/naphthalene sulfonic acids condensation product mentionedin column 5, lines 16-32. of Example 1 and 0.25 g. per liter of 80%acetic acid.

1 In this way, valuable greenish yellow dyeings which so3H S0311 SO Hhave very good wet fastness properties are obtained.

100 parts of urea 10 parts of the sodium salt of m-nitrobenzene sulfonicEXAMPLE 4 N lon is rinted with a rintin aste of the followin 450 partsof 5% sodium .alignated solution, and comgositionlza p g p g 410 partsof water.

The goods are then dried, steamed and Well rinsed with 30 Parts of thedyestufi 0f the formula cold Water.

The rinsed wool is then treated for 20 minutes at CH -80 in a fresh bathwhich contains 0.75 g. per liter 3 C1 of theformaldehyde/dihydroxydiphenylsulfone/naphtha- SO H C lene sulfonicacids condensation product used in Example 3 Tr 1, supra, as well as 0.5g. per liter of aqueous acetic fi I I acid. I 6H HO3S-QNH-C o-ol In thisway, valuable red prints are obtained which 60 C1 fi have very good wetfastness properties.

EXAMPLE 3 parts of nylon are dyed in 4000 parts of a dye liquor whichcontains 1.5 parts of a dyestutf of the 5 0 parts of urea,

65 250 parts of boiling water,

45 parts of phenol,

formula 30 parts of thiodiethylene glycol,

0 3 Cl 450 parts of 5% sodium alginate solution, and N= h parts ofwater. 30311 7 The goods are then dried and steamed and rinsed, first ,yN With cold and then with 60 Warm Water. H A The rinsed goods areafter-treated in a fresh bath in the Boas NH-O 01 6 manner described inthe previous Example 3.

In this way, valuable greenish yellow prints are ohand 1 part of 80%acetic acid. 75 tained, which have very good wet fastness properties.

1 1 EXAMPLE 100 parts of wool are dyed in 4000 parts of a dye liquorwhich contains the following agents:

4 parts of a dyestuif of the formula 0.5 part of a condensation productof 1 mol of oleic acid and 2 mols of diethanolamine (Example 5 of US.Patent No. 2,089,212) and 4 parts of 80% acetic acid.

These goods are introduced at 85, dyeing is performed 0 for 10 minutesat this temperature, the bath is brought to the boil within 10 minutesand dyeing is performed at the boil for minutes.

After dyeing, the dyed goods are rinsed and treated for 20 minutes at-80 in a fresh bath which contains 0.75 g. per liter of the reactionproduct of 2 mols of N,N',N"-pentamethyl-diethylenetriamine with 3 molsof ,B,;S'-dichl0rodiethyl ether, and 0.25 g. per liter of acetic acid.In this way, valuable vivid bluish red dyeings are obtained which arevery Wet fast.

Dyeings having similar good properties are obtained if, in the aboveexample, instead of the reaction product mentioned, anitrogen-containing condensation product of 34 parts of dicyanodia midewith 5.5 parts of ammonium chloride, 18 parts of urea and 80 partsformaldehyde is used in the after-treatment liquor and otherwise thesame procedure is followed.

If, instead of the dyestuff mentioned in the example, those given incolumn 2 of Table II are used and other- Wise the procedure described inthe example is followed, then corresponding wool dyeings as given incolumn 3 are obtained.

TABLE II No. Dyestufi Shade on Wool 1 CH3 Greenish 1 01 yellow. N=O 1H038 O O-N:N I N N N-C ll 1 HO3S- NHO C-Ol l Cl CH 2 (I31 Reddish yellowG S 03H I N=N NHG C-Ol N OH:

3 $1 Rod.

C\ 1E1 N HO NH-C C-Cl S03H SOaH SO3H 4 (H) NH; Blue.

ll I 0 NH S 0 3H SIO 3H NH-C (lJNH O I O1 5 (I) H S10 3H Scarlet;

01 S 0 11- S 0311 I N-C I NHC\ /N TABLE II-Continued N0. Dyestufi Shadeon wool 14 ()1 Blue.

H038 (I) Qu ITIHO /N l N=o N=N N=N I NH- S 0 all H038 SO3H EXAMPLE 6EXAMPLE 8 W001 is printed with a printing paste of the followingcomposition: 30 parts of the dyestutf of the formula 100 parts of urea,

10 parts of the sodium salt of m-nitrobenzene sulfonic acid,

450 parts of sodium alginate solution, and

410 parts of water.

The goods are then dried, steamed and well rinsed with cold water.

The rinsed wool is after-treated as described in Example 1. In this way,valuable, vivid bluish red prints are obtained which have very good wetfastness properties.

Similar results are obtained if, instead of the reaction products asdescribed in Example 1, a nitrogen-containing condensation product of 34parts of dicyano-diamide with 12 parts of ammonium chloride, 12 parts ofurea and 80 parts of formaldehyde are used.

EXAMPLE 7 100 parts of nylon are dyed in 4000 parts of a dye liquorwhich contains 1.5 parts of a dyestufi of the formula and 1 part of 80%acetic acid.

The goods are introduced at 40, dyeing is performed for minutes at thistemperature, the bath is brought to the boil within 30 minutes anddyeing is continued for 45 minutes at boiling temperature.

After dyeing, the goods are Well rinsed and then treated in a fresh bathfor minutes at 6080 which contains 0.75 g. per liter of the reactionproduct of 2 mols of N,N',N"-pentamethyl diethylene-triamine and 3 molsof fl,[3-dichlorodiethyl ether, and also 0.5 g. per liter of 40% aceticacid. In this way, valuable greenish yellow dyeings which have very goodwet fastness properties are obtained.

Similarly good dyeings are obtained if, in the above example,nitrogen-containing condensation product of 34 parts of dicyanodiamidewith 11 parts of ammonium chloride, 12 parts of urea and 80 parts offormaldehyde is used in the after-treatment bath instead of the reactionproduct mentioned and otherwise the same procedure is followed.

Nylon is printed with a printing paste of the following composition: 30parts of the dyestufi' of the formula 50 parts of urea,

250 parts of boiling water,

45 parts of phenol,

30 parts of 'thiodiethylene glycol,

450 parts of 5% sodium alginate solution and 145 parts of water Thegoods are then dried, steamed and rinsed first with cold and then with60 warm water.

The rinsed goods are after-treated as described in EX- ample 3. In thisway, valuable greenish yellow prints which have very good wet fastnessproperties are obtained.

Similar results are further obtained if, instead of the reaction productas described in Example 3, a reaction product obtained fromcorresponding amounts of N,N- tetramethyl-ethylene-diamine and 7,7dichloropropylether or 1,4-dibromobutane or corresponding amounts ofN,N'-tetramethyl-tetramethylene-diamine and glycoldichlorohydrin isused.

We claim:

1. In a process for producing fibers, the improvement comprising (I)introducing polyamide fibers freshly colored by heating and therebyreacting said fibers in an aqueous acid medium with reactive dyestuflfwhich contains at least one mobile substituent capable of being splitoff as anion, after coloration and prior to drying, into an aqueoussolution the solute of which consists essentially of the condensationproduct of (a) a member selected from the group consisting ofdichloroalkane of from 2 to 7 carbon atoms, dibromo-alkane of from 2 to7 carbon atoms, and dichloro-dialkylether with a total of from 4 to 8carbon atoms, with (b) a tertiary saturated aliphatic amine with a totalof from 6 to 24 carbon atoms and from 2 to 4 amino nitrogen atoms, insuch molar ratio of (a): (b) that approximately one halogen atom ispresent in the condensation reaction for every amino nitrogen atom; (II)adjusting the pH of the aqueous solution to about 4 to 5.5, by theaddition of acid, and

(III) heating the resulting acidified aqueous solution and the coloredfibers therein for about 10 to 60 minutes, at a temperature of fromabout 20 to C.

colored polyamide 2. The improvement described in claim 1, wherein thecondensation product is that of 2 moles of N,N,N"-pentamethyl-diethylenetriamine and 3 moles of }9,,8-dichlorodiethylether.

3. The improvement described in claim 1, wherein the tertiary saturatedaliphatic amine is a member selected from the group consisting ofN,N'-tetra-lower alkyl-hexamethylene diamine, N,N',N"-penta-loweralkyldiethylene triamine, and N,N,N,N"'-hexa-loweralkyltriethylene-tetramine.

4.;f1'he improvement described in claim 1, wherein the acid added instep (II) is a member selected from the group consisting of acetic acidand formic acid.

5. The improvement described in claim 1, wherein, in step (II), the pHis adjusted to about 4.5 to 5.

6. The improvement described in claim 1, wherein the aqueous acidsolution and fibers therein are heated in step (111) at a temperature ofabout 60 to 85 C.

7. The improvement described in claim 1, wherein said reactive dyestuffcontains a halogen-substituted pyrimidylamino reactive dyestuif radicaland from 2 to 3 sulfonic acid groups.

8. The improvement described in claim 1, wherein said polyamide fibersare wool.

'9. The improvement described in claim 1 wherein References Cited UNITEDSTATES PATENTS 3,104,933 9/1963 Mendelsohn et a1. 885 3,198,595 8/1965Mawson et a1. 818

FOREIGN PATENTS 1,277,635 10/ 1961 France.

894,237 10/1953 Germany.

OTHER REFERENCES L. Diserens: The Chemical Technology of Dyeing andPrinting, v01. 2, 1951, pp. 318, 319 and 336.

GEORGE F. LESMES, Primary Examiner T. J. HERBERT, IR., AssistantExaminer US. Cl. X.R.

